1. Field of the Invention
The present invention relates to a receiver, and more particularly, it relates to a receiver comprising a receiver body connected with an antenna.
2. Description of the Background Art
A receiver comprising a receiver body connected with an antenna is known in general, as disclosed in each of Japanese Patent laying-Open Nos. 2002-122651, 2006-25199 and 2006-13973, for example.
The aforementioned Japanese Patent Laying-Open No. 2002-122651 discloses a GPS receiver comprising a receiver body including an antenna connection state detecting portion. In this GPS receiver described in Japanese Patent Laying-Open No. 2002-122651, the antenna connection state detecting portion detects a voltage between the receiver body and the antenna, and determines whether the antenna connected to the receiver body is an active antenna or a passive antenna through the level of the voltage. Thus, the GPS receiver can operate correspondingly to the determined antenna.
The aforementioned Japanese Patent Laying-Open No. 2006-25199 discloses a television broadcasting receiver comprising a receiver body including antenna identification means. In this television broadcasting receiver described in Japanese Patent Laying-Open No. 2006-25199, the antenna identification means determines whether an antenna connected to the receiver body is a unidirectional antenna or a multidirectional antenna. The unidirectional antenna can receive signals only in a single direction, while the multidirectional antenna can receive signals in a plurality of directions.
The aforementioned Japanese Patent Laying-Open No. 2006-13973 discloses a digital television broadcasting signal receiver. This digital television broadcasting signal receiver described in Japanese Patent Laying-Open No. 2006-13973 is so formed as to determine whether an antenna connected to the body thereof is a unidirectional antenna or a multidirectional antenna through the difference in receiving strength between a signal, included in signals received by the antenna, in a direction maximizing the receiving strength and another signal in a direction opposite to the direction maximizing the receiving strength.
However, the aforementioned Japanese Patent Laying-Open No. 2002-122651 describing the GPS receiver neither discloses nor suggests a function of determining whether or not the antenna is connected to the receiver body. Even when no antenna is connected to the receiver body, therefore, power may conceivably be supplied to an antenna connection portion of the receiver body. Thus, power consumption is disadvantageously increased.
Each of the aforementioned Japanese Patent Laying-Open Nos. 2006-25199 and 2006-13973 describing the television broadcasting receiver and the digital television broadcasting signal receiver respectively neither discloses nor suggests a function of determining whether or not the antenna connected to the receiver body is an active antenna. Thus, it may be impossible to determine whether or not the antenna connected to the receiver body is an active antenna.